SAN FRANCISCO (MarketWatch) -- Crude-oil futures climbed Friday to close near $53 a barrel and natural gas scored a weekly gain of almost 7%, as the energy market strengthened on forecasts for colder weather in the U.S. and speculation that major oil producers may announce measures to support prices over the weekend.

Crude for February delivery closed up $1.11 at $52.99 a barrel on the New York Mercantile Exchange.

But the contract ended the week down $3.32, or 5.9%, after closing Thursday at its weakest level since May 2005, dragged lower by a steep decline in natural-gas futures after data showed a decline in supplies that was well below the average decline for the time of year. Oil prices are down over 13% since the start of the year.

Prices were up Friday "in anticipation of a possible OPEC 'surprise' over the weekend, but the mood remains tentative," said Edward Meir, analyst at Man Financial. "With $50 crude now certainly within reach and even $40 no longer a fanciful target, it will be interesting to see how OPEC plays its cards."

A senior OPEC delegate told Dow Jones Newswires Friday that ministers are holding discussion on whether to hold an emergency meeting around Jan. 20-21. The group's next regular meeting isn't until March 15 in Vienna.

The delegate, speaking on condition of anonymity, said the cartel is considering several options, one of which is to deepen the group's existing cut of 500,000 barrels a day, effective Feb. 1, by another 500,000 barrels per day, Dow Jones reported.

The cartel is more likely to enforce the production cuts it agreed on in December as crude prices fall, making the case for a firm stance more compelling, said Meir, in a note to clients. "After all, even a group as richly endowed as OPEC cannot afford to just stand by and see $2.5 billion of collective purchasing power vaporize in just ten days," he said.

OPEC's worries

Overall, "OPEC is very worried about oil and the steep price drop," said Phil Flynn, a senior analyst at Alaron Trading, in daily commentary.

But "of course when it comes to pumping oil, they just can't seem to help themselves," he said. Tanker tracker Oil Movements reported that crude exports from OPEC members will likely climb 350,000 barrels per day to 24.5 million barrels per day in the four weeks ending Jan. 27, according to Dow Jones Newswires.

"OPEC's President Mohammed al-Hamli has called the drop in the price of oil unacceptable. He has called on better compliance from his OPEC brethren," said Flynn.

A Platts survey released Friday showed that OPEC members who are part of the cartel's output quota produced an average 27 million barrels of oil per day in December, down 70,000 barrels per day from November, but still some 700,000 barrels above OPEC's current output target.

At this point, "it may be best to let the market define a bottom for us rather than picking one; a possible technical sign of a bottom could come in the wake of an intraday price reversal, where we see a sharp sell-off in heavy volume, only for prices to reverse course and close higher on the day," said Meir.

Meanwhile, weather forecasts are promising a surge of arctic air to lead to cold temperatures across the Rockies and northern Plains and more snow for Denver, according to Accuweather. Wind-chill warnings and advisories are in effect across northern Montana and North Dakota, it said.

And news that rockets have hit the U.S. embassy in Athens may be helping to support oil prices. The rocket cause minor damage to the building but no one was injured, BBC reported.

Petroleum-product prices followed crude higher. February reformulated gasoline futures rose 4.15 cents to close at $1.432 a gallon and February heating oil added 2.32 cents to end at $1.5036 a gallon. Both contracts ended below their week-ago levels.

February natural gas rose 30.9 cents, or 4.9%, to end the day at $6.601 per million British thermal units, trading 6.7% above last week's closing level. The contract lost almost 7% on Thursday.

Analysts have attributed the gains in natural gas this week to the cold weather and forecasts for more of the same over the next few days, but market experts debate over whether the winter-like temperatures will be able to offset the warmer-than-usual weather that much of the U.S. has experienced so far this winter. See Commodities Corner.

Energy trading on Nymex will be closed on Monday in honor of Martin Luther King, Jr.'s birthday.

Meanwhile, oil-industry shares moved higher, with the Amex Oil Index
$XOI
gaining the most ground. See Energy Stocks.

In Friday's metals trading, gold futures climbed $13 an ounce Friday to end the week more than 3% higher. See Metals Stocks.

And over on the Chicago Board of Trade, March corn futures climbed to their highest level ever on the exchange after the U.S. Department of Agriculture cut its forecast on the 2006/2007 corn crop. See full story.

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